fidZddlmZddlZddlmZddlmZm Z m Z dgZ dZ e de d ej d dd ZdS)uBFunctions for computing the Kernighan–Lin bipartition algorithm.)countN) is_partition) BinaryHeapnot_implemented_forpy_random_statekernighan_lin_bisectionc# Kttfx\}} ttD]B\}}}tfd|D} |||r|n| C fd}d} d} |rd|rf|\}}||||\} } ||| | || zz } | dz } | | || ffV|r|`dSdSdSdS)z This is a modified form of Kernighan-Lin, which moves single nodes at a time, alternating between sides to keep the bisection balanced. We keep two min-heaps of swap costs to make optimal-next-move selection fast. c38K|]\}}|r|n| VdS)N).0vwsides /var/www/development/aibuddy-work/election-extract/venv/lib/python3.11/site-packages/networkx/algorithms/community/kernighan_lin.py z'_kernighan_lin_sweep..s6>>da$q')QQr>>>>>>c|D]P\}}|}||}|&|d||ur| n|zz }|||dQdS)NT)getinsert) costs_xxyrcosts_ycost_ycostsedgesrs r _update_costsz+_kernighan_lin_sweep.._update_costss|!H 0 0DAqDGnG[[^^F!!W%7%7rrQ??q&$///  0 0rrN)rziprsumrpop)rrcosts0costs1uside_uedges_ucost_uritotcostr cost_vrs`` @r_kernighan_lin_sweepr, s (\\:<<77NFFU!%''477??67>>>>g>>>>> f Q& =vg>>>>0000000 AG !V!JJLL 6 fa   JJLL 6 fa   6F?" Qq1a&     !V!!!!!!!!!rdirectedweight) edge_attrs c^t}t}||dt|D|dg|dzzdg|dzdzzz}nq |\}} n.#tt f$r} t jd| d} ~ wwxYwt|| fst jddg|z}|D] } d|| < rfd|D} nfd |D} t|D]X} tt| |}t|\}}}|dkrn|d|D]\}}\}}d||<d||<Yd t||D}d t||D} || fS) uPartition a graph into two blocks using the Kernighan–Lin algorithm. This algorithm partitions a network into two sets by iteratively swapping pairs of nodes to reduce the edge cut between the two sets. The pairs are chosen according to a modified form of Kernighan-Lin [1]_, which moves node individually, alternating between sides to keep the bisection balanced. Parameters ---------- G : NetworkX graph Graph must be undirected. partition : tuple Pair of iterables containing an initial partition. If not specified, a random balanced partition is used. max_iter : int Maximum number of times to attempt swaps to find an improvement before giving up. weight : key Edge data key to use as weight. If None, the weights are all set to one. seed : integer, random_state, or None (default) Indicator of random number generation state. See :ref:`Randomness`. Only used if partition is None Returns ------- partition : tuple A pair of sets of nodes representing the bipartition. Raises ------ NetworkXError If partition is not a valid partition of the nodes of the graph. References ---------- .. [1] Kernighan, B. W.; Lin, Shen (1970). "An efficient heuristic procedure for partitioning graphs." *Bell Systems Technical Journal* 49: 291--307. Oxford University Press 2011. ci|]\}}|| Sr r )r r)r s r z+kernighan_lin_bisection..cs 0 0 0daQ 0 0 0rNrrrzpartition must be two setszpartition invalidc^g|])}fd|D*S)cg|]:\}}|tfd|Df;S)c3DK|]}|dVdS)rNr)r er/s rrz@kernighan_lin_bisection....us1DDAquuVQ//DDDDDDr)r!values)r r%dindexr/s r z6kernighan_lin_bisection...ts[   Aqq3DDDDDDDDDE   ritemsr r Gr<r/s rr=z+kernighan_lin_bisection..ss]         aDJJLL      rc^g|])}fd|D*S)cRg|]#\}}||df$Srr8)r r%r9r<r/s rr=z6kernighan_lin_bisection...|s4 C C CdaeAhfa(( ) C C Crr>r@s rr=z+kernighan_lin_bisection..{sJ   HI C C C C Cadjjll C C C   rc$h|] \}}|dk |S)rr r r%ss r z*kernighan_lin_bisection..!333tq!AFFFFFrc$h|] \}}|dk |SrDr rFs rrHz*kernighan_lin_bisection..rIr)lenlistshuffle enumerate TypeError ValueErrornx NetworkXErrorr is_multigraphranger,minr )rA partitionmax_iterr/seednlabelsrABerrarr)rmin_costmin_i_r%r r<s` ` @rrr+s\j AA !WWFLL 0 0i// 0 0 0Esa1f~A!| 44 JDAqq:& J J J"#?@@c I JA1v&& 8"#677 7sQw  ADqNN                  MS   8__)%6677 ZZ% q== E!&5&M  LAq&1aDGDGG  43s64((333A33s64((333A a4Ks*A00BBB)Nr1r/N)__doc__ itertoolsrnetworkxrQ-networkx.algorithms.community.community_utilsrnetworkx.utilsrrr__all__r, _dispatchablerr rrrisHHFFFFFFKKKKKKKKKK $ %!!!>Z  X&&&]]]'&! ]]]r